Speed change gear device

ABSTRACT

A speed change gear device which comprises a relatively small number of planetary gears and associated parts and which is especially applicable to the transmission mechanism of a smallersized automotive vehicle. The speed change gear device employs additional brake means to fix an input member of a planetary gear train to the gear case to furnish a greater speed change ratio or a greater number of speed change steps without increasing the number of gears in the planetary gear train.

United States Patent [191 Uozumi et al.

[ 1 3,733,928 1 May 22, 1973 Inventors: Sumio Uozumi, Toyota; KoichiroKirosawa, Kariya, both of Japan [73] Assignee: Toyota Jidosha KogyoKabushika Kaisha, Aichi-ken, Japan [22] Filed: June 2, 1970 [21] Appl.No.: 42,661

[30] Foreign Application Priority Data June 3, 1969 Japan ..44 4 2929 52Us. 01 ..74/753, 74/763 [51] Int. Cl ..F16h 57/10 [58] Field of Search..74/753, 763

[56] References Cited UNITED STATES PATENTS 1,037,808 9/1912 Trowbridge..74/763 1,721,123 7/1929 Kamper ..74/763 2,371,574 3/1945 Swennes..74/763 X 2,571,448 10/1951 Hobbs 2,856,796 10/1958 Miller 3 ,482,46912/ 1 969 Mori 3,010,343 11/1961 Orr et al......

3,425,300 2/1969 Ohya et a]. ..74/763 Primary Examiner-Arthur T. McKeonAtt0meyHarry G. Shapiro [57] ABSTRACT 6 Claims, 27 Drawing Figures SPEEDCHANGE GEAR DEVICE BACKGROUND OF THE INVENTION 1. Field of the InventionThis invention relates to a speed change gear device, and moreparticularly to a speed change gear device which comprises an inputshaft and an output shaft concentrically disposed within a gear case,first and second clutch means disposed between said input shaft and saidoutput shaft and connected to said input shaft, and a planetary geartrain disposed between said input and output shafts and including afirst and a second input gear member connected to said first and secondclutch means, and an output gear member connected to said output shaft.

2. Description of the Prior Art In order that a great accelerating forceor tractive force may be obtained with a vehicle having a prime mover ofsmall output, the reduction ratio of the speed change gears must beincreased. In other word, the number of speed change gears must beincreased. With a speed change gear device having planetary gears, ithas generally been necessary to increase the number of the planetarygears in a composite or single planetary gear train and accordingly thenumber of mating members in order to increase a certain number of speedchange steps by one step.

SUMMARY OF THE INVENTION The object of the present invention is toprovide a speed change gear device which eliminates the need to increasethe number of planetary gears or to substantially increase the number ofother parts and which is especially applicable to the transmissionmechanism of a smaller-sized automotive vehicle.

According to the present invention, there is provided a speed changegear device which comprises an input shaft and an output shaftconcentrically disposed within a gear case, first and second clutchmeans disposed between said input shaft and said output shaft andconnected to said input shaft, and a planetary gear train disposedbetween said input and output shafts and including a first and a secondinput gear member connectedto said first and second clutch means, and anoutput gear member connected to said output shaft, characterized by theprovision of first and second brake means for fixing said first andsecond input gear members respectively to said gear case to selectivelyoperate said clutch means and said brake means, whereby said outputshaft is provided with a combination of speed change ratios having arequired number of speed change steps.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 7 are schematic diagramsshowing seven examples of power trains used with existing typicalplanetary gear type speed change systems;

FIG. 8 is a schematic diagram showing the power train of the planetarygear type speed change device according to the first embodiment of theinvention;

FIG. 8A is a schematic diagram showing the power train according to asecond embodiment of the invention; I

FIG. 9 is a schematic diagram showing the power train according to athird embodiment of the invention;

FIG. 9A is a schematic diagram showing the power train according to afourth embodiment of the inventron;

FIG. 10 is a schematic diagram showing the power train according to afifth embodiment of the invention;

FIG. 10A is a schematic diagram showing the power train according to asixth embodiment of the invention;

FIG. 11 is a schematic diagram showing the power train according to aseventh embodiment of the inventron;

FIG. 11A is a schematic diagram showing the power train according to aneighth embodiment of the invention;

FIG. 12 is a schematic diagram showing the power train according to aninth embodiment of the invention;

FIG. 12A is a schematic diagram showing the power train according to a10th embodiment of the invention;

FIG. 13 is a schematic diagram showing the power train according to an11th embodiment of the inventron;

FIG. 13A is a schematic diagram showing the power train according to a12th embodiment of the invention;

FIG. 14 is a schematic diagram showing the power train according to a13th embodiment of the invention;

FIG. 14A is a schematic diagram of the power train according to a 14thembodiment of the invention;

FIG. 15 is a chart illustrating the operational sequence of the clutchmeans and brake means-in various speed change steps according to thefirst to 10th embodiments;

FIG. 16 is a, chart illustrating such operational sequence according tothe 11th and 12th embodiments;

FIG. 17 is a chart illustrating such operational sequence according tothe 13th and 14th embodiments;

FIG. 18 is a cross-sectional view showingthe lefthand portion of thefirst and second embodiments;

FIG. 19 is a cross-sectional view showing the righthand portion of thefirst, third, fifth, seventh, ninth, 11th and 13th embodiments each; and

FIG. 20 is a cross-sectional view showing the righthand portion of thesecond, fourth, sixth, eighth, 10th, 12th and 14th embodiments each. 1

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention will now bedescribed in connection with the accompanying drawings, in which similarnumerals designate similar parts."

The first and second embodiments of the present invention will first bedescribed. Referring to FIG. 1, there is shown a first example of thepower train used with the existing typical planetary gear typespeedchange device. This power train includes an input shaft 1, driveplates 11 splined to the input shaft 1, an intermediate shaft 2, anddriven plates 21 splined to the intermediate shaft and disposed inalternate relationship with the drive plates 11. The drive plates 11 andthe driven plates 21 together form a first clutch means C1. The powertrain further includes drive plates 12 splined to the input shaft 1, aclutch drum 3, and driven plates 31 splined to the clutch drum 3 anddisposed in alternate relationship with the drive plates 12. The driveplates 12 and the driven plates 31 together form a second clutch meansC2. An input sun gear 22 is secured to the intermediate shaft 2 and areverse sun gear 32 is secured to the drum 3. A carrier 5 has an idlegear 232 mounted for rotation thereon by a pin of the carrier,

the idle gear engaging the reverse sun gear 32. An output sun gear 41 issecured to an Output shaft 4. A long pinion gear 100 is mounted forrotation on a pin of the carrier 5, and has teeth 132, 122 and 141meshing with the idle gear 232, input sun gear 22 and output sun gear41, respectively. First brake means Bl is'provided for stopping theclutch drum 3, and second brake means B2 is provided for stopping thecarrier 5.

The first embodiment of the present invention is shown in FIG. 8. Theleft-hand portion of FIG. 8 is similar to FIG. 1. The right-hand oroutput shaft portion includes a drive gear 42 secured to the outputshaft 4, a driven gear 43 meshing with the drive gear 42, an outputshaft 44 secured to the driven gear 43 and connected to a propellershaft (not shown), a drum 23 secured to the intermediate shaft 2, and athird brake means B3 for stopping the drum 23.

The first embodiment will now be described with reference to thecross-sectional view of FIG. 18, which shows the vleft-hand portion ofthe planetary gear type speed change device having the power train asshown in FIG. 8 according to the first embodiment of the presentinvention. Reference is also made to FIG. 19 which shows, in crosssection, the right-hand portion of the first embodiment whose powertrain is shown in FIG. 8.

In FIG. 18, the input shaft 1 is rotatably mounted within a case 6. Aclutch drum 13 is splined to the input shaft 1. The drive plates 11 areslidably splined to the clutch drum 13. A clutch hub 24 is splined tothe intermediate shaft 2, and circumferentially of the clutch hub 24there are driven plates 21 which are splined thereto and disposed inalternate relationship with the drive plates 11 as described previously.A clutch piston 14 is slidably mounted within the clutch drum 13 todefine a hydraulic chamber, e.g., an oil pressure chamber between thepiston and the drum. A spring bearing mem- 132 of the long pinion gear100. The input sun gear 22 meshes with the teeth 122 of the long piniongear 100. The output shaft 4 is rotatably carried by the carrier 5 andthe output sun gear 41 is secured to the output shaft 4. The output sungear 41 is engaged by the teeth 141 of the long pinion gear 100. Thefirst brake means 131 is arranged to fix the clutch drum 3 to the case 6and the second brake means B2 is arranged to fix the carrier 5 to thecase 6.

Referring to FIG. 19, the drive gear 42 is secured to the output shaft 4as described with respect to FIGS. 8-14. The output shaft 44 isrotatably connected to the case 6 and driven from a drive wheel (notshown). The driven gear 43 is secured to the output shaft 44 and mesheswith the drive gear 42. The drum 23 is secured to the intermediate shaft2, and third brake means B3 is arranged to fix the drum 23 to the case6.

The second embodiment of the present invention comprises an arrangementas shown in FIG. 8A. A drive gear 142 is secured to the output shaft 4and meshes with a driven gear 143 which has a pin secured thereto. Onthat pin there are rotatably mounted gears 144a and 144b which aremesh-engaged by gears 145a and 145b respectively mounted on drive shafts146a and 146b. The drum 23 is secured to the intermediate shaft 2 andthe third brake means B3 is arranged to fix ber 16 is secured to theclutch drum 13 by means of a snap ring 17, and a return spring 15 ismounted between the clutch'piston 14 and the spring bearing member.First clutch means C1 comprises the drive plates 11, driven plates 21,clutch hub 24, clutch piston 14, return spring 15 spring bearing member16, and clutch drum l3.

Still referring to FIG. 18, the drive plates 12 are slidably splined tothe clutch drum 13 circumferentially l2 driven plates 31,-clutch drum 3,clutch piston 34, return spring 35 and spring bearing member 36. Asdescribed with respect to FIG. 1', the input sun gear 22 is secured tothe intermediate shaft 2 and the reverse sun gear 32 is secured to theclutch drum 3. The carrier 5 is rotatably mounted within the case 6, andcarries thereon a long pinion pin 51. Rotatably mounted on the longpin-ion pin 51 is a long pinion gear 100. The carrier 5 also carriesthereon a short pinion pin 52, on which an idle gear 232 is rotatablymounted. The idle gear 232 meshes with the reverse sun gear 32 and theteeth the drum 23 to the case 6.

The second embodiment will now be described with reference to thecross-sectional views thereof as shown in FIGS. 18 and 20. The left-handportion or planetary gear type speed change device portion of the secondembodiment is identical with that of the first embodiment, and FIG. 18corresponds to the cross-sectional view of the same portion according tothis alternative embodiment; FIG. 20 is a cross-sectional view showingthe right-hand or output shaft portion of the second embodiment whosepower train is schematically shown in FIG. 8a. In FIG. 20, numeral 4represents the output shaft identical with that indicated by 4 in FIG.20, 142 the drive gear secured to the output shaft 4, 147 a housingrotatably mounted on the casing 6, and 143 the driven gear secured tothe housing 147 and meshengaged by the drive gear 142. Numeral 140designates a pin carried by the housing l47,and 144a and 144b gearsrotatably mounted on the pin 140 and engaged by gears 145a and l45brespectively, which in turn are secured to the drive shafts 146a and146k respectively and driven from a drive wheel (not shown). Numeral 23designates the drum secured to 'the intermediate shaft 2, and B3 is thethird brake means arranged to fix the drum 23 to the case 6. I

The output shaft portion shown in FIG. 19 also forms the output shaftportion of each of the third, fifth, seventh, ninth, 11th and 13thembodiments which will be described later, and the output shaft portionshown in FIG. 20 forms such portion of each of the fourth, sixth,

- eighth, 10th, 12th and 14th embodiments which will also be describedlater. 1

The first example of the power train shown in FIG. 1 will now becompared in operation with the first and secondembodiments. In FIG. 1,the input shaft 1 is driven from a prime mover directly or by a torqueconverter, fluid couplingand clutch means (not shown). If the firstclutch means C1 is brought into its engaged position, the input shaft 1will drive a first input member or intermediate shaft 2 through thefirst clutch means Cl and accordingly the inputsun gear 22 secured tothe intermediate shaft 2 is driven. With the carrier 5 fixed to the gearcase by the second brake means B2, the drive force of the input sun gear22 will be transmitted through the teeth 122 of the long pinion gear 100to the teeth 141 of the same long pinion gear 100 and further to theoutput sun gear 41 engaging the teeth 141, whereby the output shaft 4 isrotated to provide a first speed change ratio. Subsequently, with thefirst clutch means C1 in the engaged position, the second brake means B2is released and the first brake means B1 is actuated to fix a secondinput member or clutch drum 3 to the gear case. As a result, the driveforce of the first input member or input sun gear 22 is transmitted tothe long pinion gear 100 and idle gear 232, whereby these two gearsrevolve about the reverse sun gear 32 and the carrier 5 also rotates.The output sun gear 41 engaging the rotating and revolving long piniongear 100 is rotated thereby, whereby the output shaft 4 connected to theoutput sun gear is provided with a second speed change ratio. With thefirst clutch means C1 still in the engaged position, the first brakemeans B1 is subsequently released and the second clutch means C2 isactuated to engage the clutch drum 3 with the input shaft 1, whereby theinput gear 22 and reverse gear 32 are driven together to thereby preventthe gears of the planetary gear train from rotating relative to oneanother and bring these gears into directly connected relationship,whereby the input shaft 1 and output shaft 4 effect the same rotation toprovide a third speed change ratio. The first clutch means C1 is thenreleased and the second clutch .means C2 .is brought into its engagedposition to transmit the drive force from the input shaft 1 to thesecond input member or clutch drum 3 and reverse sun gear 32 while thesecond brake means B2 is actuated to fix the carrier 5 to gear case,whereby the drive force of the reverse sun gear 32 is transmittedthrough the idle gear 232 to the teeth 132 and teeth 141 of the longpinion gear 100 and further to the output sun gear 41 engaging the teeth141. Thus, the output shaft 4 is now rotated in the opposite directionto provide a reverse speed change ratio.

The operation of the first and second embodiments of the presentinvention will now be explained. FIGS. 8 and 8A the second clutch meansC2 is brought into its engaged position to transmit the drive force ofthe input shaft 1 to the second input member or clutch drum 3 andreverse sun gear 32. The third brake means B3 is actuated so that thedrum 23 secured to the first input member or intermediate shaft 2 isengaged with the gear case, whereby the drive force of the reverse sungear 32 is transmitted through the idle gear 232 to the teeth 132 of thelong pinion gear 100. With the rotation of the long pinion gear 100, theteeth 122 thereof rotates and revolves about the input sun gear 22engaged with the case by the third brake means B3, and the carrier 5 isalso rotated in the same direction. The drive force is furthertransmitted to the output sun gear 41 engaging the teeth 141 of therotating and revolving long pinion gear 100, whereby the output shaft 4is provided with a first speed change ratio. The second, third andfourth speeds provided in the FIGS. 8 and 8A arrangement correspond tothe first, second and third speeds provided by the FIG. 1 arrangement,and the reverse speed change ratio is the same as described with respectto FIG. 1.

The drive force thus provided in each speed change step according to thefirst embodiment is transmitted, as noted in FIG. 8, from the drive gear42 secured to the output shaft 4 through the driven gear 43 engagingtherewith to the output shaft 44, and further through a propeller shaftand a differential means to unshown drive wheel (not shown), which thusdrives the vehicle.

The drive force in each speed change step according to the secondembodiment is transmitted, as noted in FIG. 8A, through differentialmeans 140 to the output shafts 146a and 146b which thus drive thevehicle.

The third and fourth embodiments of the invention will now be described.FIG. 2 shows the second example of the power train used with theexisting typical planetary gear type speed change device. In FIG. 2,numeral 1 denotes an input shaft, 11 drive plates splined to the inputshaft 1, 2 an intermediate shaft, and 21 driven plates splined to theintermediate shaft 2 and disposed in alternate relationship with thedrive plates 11. The drive plates 11 and driven plates 21 together formfirst clutch means Cl. Numeral 12 designates drive plates splined to theinput shaft 1, 3 a clutch drum and 31 driven plates splined to theclutch drum 3 and disposed in alternate relationship with the driveplates 12. The drive plates 12 and driven plates 31 together form secondclutch means C2. Numeral 22 designates an input sun gear secured to theintermediate shaft 2, 32 a reverse sun gear secured to the clutch drum3, and 5a a carrier for carrying a short pinion gear 232 for rotation ona pin of the carrier, the short pinion gear 232 engaging with thereverse sun gear 32. Numeral a represents a long pinion gear carried bythe carrier 50 for rotation on a pin thereof and engaging the shortpinion gear 232 and input sun gear 22, and 101a is a ring gear engagingthe long pinion gear 100a. Bl denotes first brake means arranged to fixthe clutch drum 3, and B2 second brake means arranged to fix the ringgear 101a. Numeral 4 represents an output shaft secured to the carrier5a. The third embodiment is shown in FIG. 9, the input portion of whichis similar to FIG. 2. The fourth embodiment is shown in FIG. 9A.

The operation of the power train will now be described by way ofcomparison between the second example shown in FIG. 2 and the third andfourth embodiments of the present invention. In FIG. 2, the input shaft1 is driven from a prime mover in the same way as described with respectto FIG. 1. If the first clutch means C1 is brought into its engagedposition, the input shaft 1 will drive a first input member orintermediate shaft 2 via the first clutch means C1 and accordingly drivethe input sun gear 22 secured to the intermediate shaft 2. If the ringgear 101a is fixed to the gear case by the second brake means B2, thelong pinion gear 100a engaging the input sun gear 22 will be rotated inthe opposite direction to the input shaft 1 while revolving in the samedirection therewith due to the engagement with the ring gear 101a. Thisrevolution of the input sun gear 22 causes the carrier 5a to rotate tothereby provide the output shaft with a first speed change ratio. Withthe first clutch means C1 in the engaged position, the second brakemeans B2 is then released to fix a second input member or clutch drum 3and reverse sun gear 32 to the gear case, whereby the drive force fromthe input sun gear 22 is transmitted through the long pinion gear 100aengaging therewith and through the idle gear 232 engaging the gear 10011to the reverse sun gear 32. Thus, the idle gear 232 is caused to rotateand revolve in the same direction as the input shaft 1. This rotation ofthe idle gear causes the carrier a to rotate to thereby provide theoutput shaft 4 with a second speed change ratio. With the first clutchmeans C1 still in the engaged position, the first brake means B1 issubsequently released and the second clutch means C2 is actuated toengage the second input member or clutch drum 3 with the input shaft 1,so that the input sun gear 22 and reverse sun gear 32 are driventogether to prevent the gears of the planetary gear train from rotatingrelative to one another. Thus the input shaft 1 and output shaft 4effect the same rotation to provide a third speed change ratio. If thefirst clutch means C1 is released and the second clutch means is broughtinto its engaged position to thereby transmit the drive force of theinput shaft 1 to the second input member or clutch drum 3 and reversesun gear 32, and the second brake means B2 is actuated to fix the ringgear 101a to the gear case, then the drive force of the reverse sun gear32 will be transmitted through the idle gear 232 to the long pinion gear100a, which is thus caused to rotate in thesame direction as the inputshaft 1 but revolve in the opposite direction because the long piniongear 100a is in engagement with the ring gear 101a fixed in thedescribed manner. This rotation of the long pinion gear 101a causes thecarrier 5a to rotate to thereby provide the output shaft 4 with areverse speed change ratio.

The operation will now be described with respect to the third and fourthembodiments of the present invention as shown in FIGS. 9 and 9A. Thesecond clutch means C2 is first brought into its engaged position totransmit the drive force of the input shaft 1 to the second input memberor clutch drum 3 and reverse sun gear 32, and the third brake means B3is actuated to fix to the gear case the drum 23 secured to the firstinput member or intermediate shaft 2. Thus the drive force of thereverse sun gear 32 is transmitted through the idle gear 232 engagingtherewith to the long pinion gear 100a engaging the gear 232, wherebythe long pinion gear 100a is caused to rotate and revolve around theinput sun gear 22 in the same direction as the input shaft 1. Therevolution of the long pinion gear 1000 causes the carrier 5a to rotateto thereby provide the output shaft 4 with a first speed change ratio.The second, third and fourth speeds provided in the embodiments of FIGS.9 and 9A correspond to the first, second and third speeds provided bythe FIG. 2 arrangement, and the reverse speed change ratio is the sameas described with respect to FIG. 2.

The fifth and sixth embodiments of the present invention will now bedescribed. Referring to FIG. 3 which shows the third example of thepower train used with the existing typical planetary gear type speedchange device, numeral 1 designates an input shaft, 11 drive platessplined to the input shaft 1, 2 an intermediate shaft, and 21 drivenplates splined to the intermediate shaft 2 and disposed in alternaterelationship with the drive plates 11. The drive plates 11 and drivenplates 21 together form first clutch means Cl. Numeral 12 denotes driveplates splined to the input shaft 1, 3 a clutch drum, and 31 drivenplates splined to the clutch drum 3 and disposed in alternaterelationship with the drive plates 12. The drive plates 12 and drivenplates 31 together form second clutch means C2. Numeral 22 designates aninput sun gear secured to the intermediate shaft 2, 5b a carrier, 222 ashort pinion gear mounted for rotation on a pin of the carrier 5b andengaging the input sun gear 22, 32 a reverse sun gear secured to thedrum 3, b along pinion gear mounted for rotation on a pin of the carrier5b and engaging the short pinion gear 222 and reverse sun gear 32, and10112 a ring gear engaging the long pinion gear 100b. Numeral 4 denotesan output shaft secured to the ring gear 101b, and B1 and B2respectively denote first brake means for fixing the clutch drum 3 andsecond brake means for fixing the carrier 5b.

Comparison will be made in operation between the third example shown inFIG. 3 and the fifth and sixth embodiments as shown in FIGS. 10 and 10a.In FIG. 3, the input shaft 1 is driven from a prime mover in the mannerdescribed with respect to FIG. 1. When the first clutch means C1 isbrought into its engaged position, the input shaft 1 drives a firstinput member or intermediate shaft 2 through the first clutch means Cland accordingly drives the input sun gear 22 secured to the intermediateshaft 2. If the second brake means B2 is actuated to fix the carrier 5bto the gear case, the drive force will be transmitted through the shortpinion gear 222 engaging the input sun gear 22 to the long pinion gear100b engaging the gear 222 and further to the ring gear l01b engagingthe gear 100b, whereby the output shaft 4 secured to the ring gear 101bis provided with a first speed ratio. With the first clutch means C1remaining in the engaged position, the second brake means B2 may then bereleased and the first brake means B1 is actuated to secure to the gearcase a second input member or clutch drum 3 and reverse sun gear 32,whereby the drive force from the input sun gear 22 is transmittedthrough the short pinion gear 222 engaging therewith to the long piniongear 100b, which in turn is caused to rotate and revolve on the reversesun gear 32 in the same direction as the input shaft 1. Thus the outputshaft 4 engaged by the long pinion gear 10% is provided with a secondspeed change ratio. With the first clutch means C1 still in the engagedposition, the first brake means B1 is subsequently released and thesecond clutch means C2 is actuated to engage a second input member orthe clutch drum 3 with the input shaft 1 to thereby drive the input sungear 22 and reverse sun gear 32 together so as to prevent the gears ofthe planetary gear train 10 from rotating relative to one another. Thusthe input shaft 1 and output shaft 4 effect the same rotation to providea third speed change ratio. When the first clutch means C1 is thenreleased and the second clutch means C2 is brought into its engagedposition to transmit the drive force of the input shaft 1 to the secondinput member or clutch drum 3 and reverse sun gear 32, and the secondbrake means B2 is actuated to fix the carrier 5b to the gear case, thenthe drive force of the reverse sun gear 32 is transmitted to the longpinion gear 10012 which drives the ring gear l0lb engaging therewith,whereby the output shaft 4 is provided with a reverse speed changeratio.

The operation of the fifth and sixth embodiments of the presentinvention will now be described with reference to FIGS. 10 and 10A. Thesecond clutch means C2 is first brought into engaged position totransmit the drive force of the input shaft 1 to the second input memberor clutch drum 3 and reverse sun gear 32, and the third brake means B3is actuated so that the drum 23 secured to the first input member orintermediate shaft 2 is fixed to the gear case. Thereupon the driveforce of the reverse sun gear 32 is transmitted through the long piniongear Gb engaging therewith to the short pinion gear 222 engaging thegear 100b, whereby the short pinion gear 222 rotates and revolves on theinput sun gear 22 in the same direction as the input shaft 1. Therevolution of the short pinion gear 222 causes the ring gear 101b torotate to thereby provide the output shaft 4 with a first speed changeratio. The second, third and fourth speeds provided in the arrangementsof FIGS. 10 and 10a correspond to the first, second and third speedsprovided in the FIG. 3 arrangement, and the reverse speed change ratiois the same. The manner in which the drive force in each speed changestep according to the fifth and sixth embodiments is the same as in thefirst and second embodiments.

The seventh and eighth embodiments of the present invention will now bedescribed. FIG. 4 shows the fourth example of the power train used withthe existing typical planetary gear type speed change device. Numeral 1designates an input shaft, 11 drive plates splined to the input shaft 1,2 an intermediate shaft and 21 driven plates splined to the intermediateshaft 2 and disposed in alternate relationship with the drive plates 11.The drive plates 11 and driven plates 21 together form first clutchmeans C1. Numeral 12 denotes drive plates splined to the input shaft 1,3 a clutch drum and 31 driven plates splined to the clutch drum 3 anddisposed in alternate relationship with the drive plates 12. The driveplates 12 and driven plates 31 together form second clutch means C2.Numeral 220 designates a ring gear secured to the intermediate shaft 2,320 a reverse sun gear secured to the drum 3, 50 a carrier, 2220 apinion gear mounted for rotation on the pin of the carrier 50 andengaging the ring gear 220 and reverse sun gear 320, 60 another carrier,1610 a pinion gear mounted for rotation on a pin of the carrier 60 andengaging the reverse sun gear 320, 610 a ring gear engaging the piniongear 1610, and 4 an output shaft secured to the carrier 50 and ring gear610. B1 and B2 represent first brake means arranged to fix the clutchdrum 3 and second brake means arranged to fix the carrier 60,respectively.

The operation will be described by way of comparison between the fourthexample shown in FIG. 4 and the seventh and eighth embodiments as shownin FIGS. 11 and 11a. In FIG. 4, the input shaft 1 is driven from a primemover as in the case of FIG. 1. If the first clutch means C1 is broughtinto engaged position, the input shaft 1 will drive the first inputmember or intermediate shaft 2 via the first clutch means C1 andaccordingly drive the ring gear 220 secured to the intermediate shaft 2.If the second brake means B2 is then actuated to secure the carrier 60to the gear case, the drive force will be transmitted through the piniongear 2220 engaging the ring gear 220 to the reverse sun gear 320 andfurther through the pinion gear 1610 engaging therewith to the ring gear610. The drive force is then transmitted to the output shaft 4, which isthereby provided with a first speed change ratio. With the first clutchC1 remaining in the engaged position, the second brake means B2 issubsequently released and the first brake means B1 is actuated so thatthe second input member or clutch drum 3 and reverse sun gear 320 arefixed to the gear case. Thereupon the drive force from the ring gear 22cis transmitted to the pinion gear 2220 engaging therewith, whereby thepinion gear 2220 is rotated and revolved on the reverse sun gear 32c inthe same direction as the input shaft 1. The revolution of the piniongear 2220 causes the carrier 50 to rotate to thereby provide the outputshaft 4 with a second speed change ratio. With the first clutch means C1still in the engaged position, the first brake means B1 is then releasedand the second clutch means C2 is actuated to engage the second inputmember or clutch drum 3 with the input shaft 1, whereby the ring gear220 and reverse sun gear 320 are driven together to prevent the gears ofthe planetary gear train 10 from rotating relative to one another. Thusthe input shaft 1 and output shaft 4 effect the same rotation to providea third speed change ratio. The first clutch means Cl is subsequentlyreleased and the second clutch means C2 is brought into the engagedposition to transmit the drive force from the input shaft 1 to thesecond input member or clutch drum 3 and reverse sun gear 320 and thecarrier 60 is fixed to the gear case by the second brake means B2.Thereupon the drive force of the reverse sun gear 320 is transmittedthrough the pinion gear 1610 to the ring gear 610 engaging therewith,whereby the output shaft 4 is provided with a reverse speed changeratio.

The seventh and eighth embodiments will now be described. The secondclutch means C2 is brought into engaged position to transmit the driveforce from the input shaft 1 to the second input member or clutch drum 3and reverse sun gear 320 and the third brake means B3 is actuated sothat the drum 23 secured to the first input member or intermediate shaft2 is fixed to the gear case. Thereby the drive force of the reverse sungear 320 is transmitted to the pinion gear 2220 engaging therewith andthus the pinion gear 2220 is caused to rotate within the ring gear 220now fixed to the said case in the opposite direction to the input shaft1 while revolving in the same direction as the input shaft 1. Therevolution of the pinion gear 2220 causes the carrier 50 to rotate tothereby provide the output shaft 4 with a first speed change ratio. Thesecond, third and fourth speeds provided in the arrangements of FIGS. 11and 11A correspond to the first, second and third speeds described abovewith respect to FIG. 4, and the reverse speed change ratio is the same.The manner in which the drive force provided in each speed change stepaccording to the seventh and eighth embodiments is the same as describedwith respect to the first and second embodiments.

The ninth and 10th embodiments of the present invention will now bedescribed. FIG. 5 shows the fifth example of the power train used withthe existing typical planetary gear type speed change device and thisexample is the same in arrangement as the fourth example shown in FIG.4. The ninth embodiment is shown in FIG. 12, and the tenth embodiment isillustrated in FIG. 12A, which are similar arrangements to that of FIG.5 except for the output portion or each of these power trains. Also,these ninth and 10th embodiments are similar in operation to thepreviously described seventh and eighth embodiments.

The operational sequence of the various clutch means and brake means ineach speed change step for the first to tenth embodiments as shown inFIGS. 8 to 12 is shown in the chart of FIG. 15.

The llth and 12th embodiments of the present invention will now bedescribed. FIG. 6 shows the sixth example of the power train used withthe existing typical planetary gear type speed change device. In FIG. 6,there are shown an input shaft 1, drive plates 11 splined to the inputshaft 1, an intermediate shaft 2 and driven plates 21 splined to theintermediate shaft 2 and disposed inalternate relationship with thedrive plates 11.

The drive plates 11 and driven plates 21 together form first clutchmeans Cl. There are also provided drive plates 12 splined to the inputshaft 1, a clutch drum 3 and driven plates 31 splined to the clutch drum3 and disposed in alternate relationship with the drive plates 12. Thedrive plates 12 and driven plates 31 together form second clutch meansC2. Further provided are an input sun gear 22 secured to theintermediate shaft 2, a ring gear 32d secured to the clutch drum 3, acarrier 5d, a short pinion gear 222d mounted for rotation on a pin ofthe carrier 5d and engaging a input sun gear 22, a long pinion gear 100dmounted for rotation on the pin of the carrier 5d and engaging each ofthe short pinion gear 222d and ring gear 32:1,; and a forward sun gear61d engaging the long pinion gear 100d. First brake means B1 is arrangedto fix the clutch drum 3. A drum 6 is secured to the forward sun gear61d, and second brake means B2 is arranged to fix the drum 6. An outputshaft 4 is connected to the carrier 5d. The eleventh embodiment is shownin FIG. 13, and the 12th embodiment is illustrated in FIG. 13A, thearrangements of which are similar to that of FIG. 6 except for theoutput portion of each of the power trains.

The operation will now be described by way of comparison between thesixth example of the conventional power train shown in FIG. 6 and thellth to 12th embodiments of the present invention. In FIG. 6, the inputshaft 1 is driven from a prime mover as in the case of FIG. 1. If thefirst clutch means C1 is brought into engaged position, the input shaft1 will drive the first input member or intermediate shaft 2 via thefirst clutch means C1 and accordingly drive the input sun gear 22secured to the intermediate shaft 2. If the second brake means B2 isactuated so that the drum 6 secured to the forward sun gear 61d issecured to the gear case, the drive force of the input sun gear 22 willbe transmitted through the short pinion gear 222d engaging therewith tothe long pinion gear 100d engaging the pinion gear 222d, whereby thelong pinion gear 100d is caused to rotate and revolve on the forward sungear 61d secured to the gear case in the same direction as the inputshaft 1. This revolution of the long pinion gear 100d causes the carrier5d to rotate to thereby provide the output shaft 4 with a first speedchange ratio. With the second brake means in its engaged position, thefirst clutch means C1 is released and the second clutch means C2 isbrought into its engaged position, whereby the input shaft 1 drives thesecond input member or clutch drum 3 and'ring gear 32d through thesecond clutch means C2. The rotation of the clutch drum 3 and ring gear32d causes the long pinion gear 100d engaging the ring gear 32d torotate, whereby the long pinion gear 100d is caused to rotate andrevolve on the forward sun gear 61d secured to the gear case in the samedirection as the input shaft 1. Such revolution also causes the carrier5d to rotate to thereby provide the output shaft 4 with a second speedchange ratio. Now with the second clutch means C2 in its engagedposition, the second brake means B2 is released and the first clutchmeans C1 is engaged, the ring gear 32d and input sun gear 22 are driventogether to prevent the gears of the planetary gear train from rotatingrelative to one another. Thus the input shaft 1 and output shaft 4effect the same rotation to thereby provide a third speed change ratio.Subsequently the first clutch means Cl is engaged and the first brakemeans B1 is actuated to fix the clutch drum 3 to the gear case, wherebythe drive force of the input sun gear 22 is transmitted to the shortpinion gear 222d engaging therewith and further to the long pinion geard engaging the pinion gear 222d. Thus the long pinion gear 100d iscaused to rotate within the ring gear 32d fixed to the gear case in thesame direction as the input shaft while revolving in the oppositedirection. Such revolution of the long pinion gear 100d causes thecarrier 5d to rotate to thereby provide the output shaft with a reversespeed change ratio.

The llth and 12th embodiments of the present invention will now bedescribed with reference to FIGS. 13 and 13A. The second clutch means C2is first brought into engaged position to transmit the drive force fromthe input shaft 1 to the second input member or clutch drum 3 and ringgear 32d and the third brake means B3 is actuated so that the drum 23secured to the first input member or intermediate shaft 2 is fixed togear case. Thereby the drive force of the ring gear 32d is transmittedthrough the long pinion gear 100d engaging therewith to the short piniongear 222d engaging the pinion gear 100d, whereby the short pinion gear222d is caused to rotate on the input sun gear 22 secured to the gearcase in the same direction to the input shaft 1 while revolving in thesame direction as the input shaft. Such revolution of the short piniongear 222d causes the carrier 5 d to rotate to thereby provide the outputshaft 4 with a fourth speed change ratio. The first to third speedsprovided in the arrangement of FIGS. 13 and 13A correspond to the firstto third speeds in the FIG. 6 arrangement. The reverse speed changeratio is the same as described with respect to FIG. 6. The manner inwhich the drive force in each speed change step according to the llthand 12th embodiments is transmitted to drive the vehicle is the same asdescribed with respect to the first and second embodiments. Theoperational sequence of the clutch means and brake means in each speedchange step according to the 11th and 12th embodiments is shown in thechart of FIG. 16.

The 13th and 14th embodiments of the present invention will be describedby way of comparison with the seventh example of the power train usedwith the existing typical planetary gear type speed change device asshown in FIG. 7. This example'of the power train includes an input shaft1, drive plates 11 splined to the input shaft 1, an intermediate shaft2, and driven plates 21 splined to the intermediate shaft 2 and disposed in alternate relationship with the drive plates 11. The driveplates 11 and driven plates 21 together form first clutch means Cl.There are further provided drive plates 12 splined to the input shaft 1,a clutch drum 3, and driven plates 31 splined to the clutch drum 3 anddisposed in alternate relationship with the drive plates 12. The driveplates 12 and driven plates 31 together form second clutch means C2. Thepower train also includes an input sun gear 22 secured to theintermediate shaft 2, a reverse sun gear 32 secured to the clutch drum3, a carrier 5e, an idle gear 200 mounted for rotation on a pin of thecarrier 5e and having teeth 222eand having teeth 122e engaging the teeth222e of the idle gear 200. The long pinion gear also has teeth ll3Zeengaging the reverse sun gear 32 and teeth I81 engaging a sun gear 81.The power train further includes fourth brake means B4, a drum 8arranged to be fixed to the gear case by the fourth brake means B4 andformed integrally with the sun gear 81, an output shaft 4, and an outputsun gear 41 secured to the output shaft 4 and engaged by the teeth 141eof the idle gear 200. Second brake means B2 is arranged to fix to thegear case the carrier 5e carrying thereon the idle gear 200 and longpinion gear 100e, and first brake means is arranged to fix to the gearcase the clutch drum 3 integral with the reverse sun gear 32. The 13thembodiment is shown in FIG. 14, and the fourteenth embodiment isillustrated in FIG. 14A, these arrangements being similar to FIG. 7except for the output portions of the power trains.

In operating the power train of FIG. 7, the input shaft 1 is driven froma prime mover in the same way as described with respect to FIG. I. Thefirst clutch means Cl is engaged so that the input shaft 1 drives thefirst input member or intermediate shaft 2 via the first clutch means Cland accordingly drives the input sun gear 22 secured to the intermediateshaft 2. If the second brake means B2 is actuated to fix the carrier 5eto the gear case, the drive force of the input sun gear 22 istransmitted to the teeth 2222 of the idle gear 200 engaging the inputsun gear 22 so that the teeth l41e of the idle gear 200 drives theoutput sun gear 41, whereby the output shaft 4 is provided with a firstspeed change ratio. Next, with the first clutch means Cl remaining inthe engaged position, the second brake means B2 is released and thefourth brake means B4 is actuated to fix to the gear case the drum 8secured to the sun gear 81, whereby the drive force from the input sungear 22 drives the teeth 222e of the idle gear 200 engaging therewithand is further transmitted to the teeth l22e of the long pinion gear100e engaging the teeth 222a. Thus the long pinion gear 100a is causedto rotate and revolve on the sun gear 81 fixed to the gear case andengaging the teeth 181 of the long pinion gear 100e, in the samedirection as the input shaft 1. Such rotation and revolution of the idlegear 200 drives the output sun gear 41 in engagement with the teeth 141eof the idle gear 200 to thereby provide the output shaft 4 with a secondspeed change ratio. With the first clutch means Cl still in the engagedposition, the fourth brake means B4 is released and the first brakemeans B1 is actuated to fix to the gear case the second input member orclutch drum 3 and reverse sun gear 32, so that the drive force from theinput sun gear 22 drives the teeth 122a of the long pinion gear 100e viathe teeth 222e of the idle gear 200 engaging the input sun gear 22. Asit receives the drive force, the long pinion gear 100e is caused torotate and revolve on the reverse sun gear 32 fixed to the gear case andengaging the teeth l32e of the long pinion gear 100s, in the samedirection as the input shaft 1. The revolution of the long pinion gear100e causes the carrier 5e to rotate and accordingly the idle gear 200on the carrier 5e revolves in the same way. Thus the output sun gearengaging the tooth 141e of the idle gear 200 has a rota tional forceimparted thereto and thereby the output shaft 4 is provided with a thirdspeed change ratio. With the first clutch means Cl still in the engagedposition, the first brake means B1 is then released and the secondclutch means C2 is actuated to engage the second input member or clutchdrum 3 with the input shaft 1 so that the input sun gear 22 and reversesun gear 32 are driven together to prevent the gears of the planetarygear train 10 from rotating relative to one another. Thus the inputshaft 1 and output shaft 4 effect the same rotation to thereby provide afourth speed change ratio. Subsequently, if the first clutch means C1 isreleased and the second clutch means C2 is engaged to transit the driveforce from the input shaft 4 to the second input member or clutch drum 3and reverse sun gear 32, and the second brake means B2 is actuated tosecure the carrier 5e to the gear case, then the drive force of thereverse sun gear 32 is transmitted to the teeth 132a of the long piniongear 1002 engaging therewith and further to the teeth 122e of the samegear e, whereby the teeth 222e of the idle gear 200 engaging the teeth122e and the teeth l41e of the same idle gear are driven to rotate theoutput sun gear 41 engaging the teeth l4le. Thus the output shaft 4secured to the output sun gear 41 is provided with a backing speedchange ratio.

The operation of the 13th and 14th embodiments of the present inventionwill now be described. In FIGS. 14 and 14A, the second clutch means C2is first brought into engaged position to transmit the drive force fromthe input shaft 1 to the second input member or clutch drum 3 andreverse sun gear 32. The third brake means B3 is then actuated to fix tothe gear case the drum 23 secured to the first input member orintermediate shaft 2. Thereupon the drive force of the reverse sun gear32 drives the teeth 132a of the long pinion gear 100e engaging therewithand is further transmitted to the teeth 122:? of the long pinion gear100:: to drive the teeth 222e of the idle gear 200 engaging therewith.The idle gear 200 is thus driven to rotate and revolve in the samedirection as the input shaft 1 on the input sun gear 22 fixed to thegear case and engaging the teeth 222e of the idle gear 200. This causesthe rotation of the output sun gear 41 engaging the teeth 141a of theidle gear 200 to thereby provide the output shaft 4 with a first speedchange ratio. The second, third, fourth and fifth speeds attained by thearrangements of FIGS. 14 and 14A correspond to the first, second, thirdand fourth speeds attained by thearrangement of FIG. 7, and the reversespeed change ratio is similar to that described with respect to the FIG.7 arrangement. The manner in which the drive force in each speed changestep according to the 13th and 14th embodiments is transmitted to drivethe vehicle is the same as in the first and second embodiments. Theoperational sequence of the clutch means and brake means in each speedchange step for the 13th and 14th embodiments is shown in the chart ofFIG. 19.

In the illustrated various embodiments of the present invention, theclutch means have been shown as multiplate clutch structure. It will beapparent that the same result may be obtained by using other clutchstructure such as single-plate clutch, conical clutch, hub clutch orelectromagnetic clutch. Also, the brake means have been shown anddescribed as band brake structure, but the same result may be attainedby. using other brake structure such as singleor multi-plate brake,conical brake, hub or pawl brake, or electromagnetic brake.

As hereinbefore described, the present invention enables the speedchange gear device to attain a greater speed change ratio or a greaternumber of speed change steps in a simple manner and without increasingthe number of required parts, thereby providing greater acceleratingforce or tractive force for a vehicle whose prime mover has a smalloutput. In the conventional planetary gear type speed change device, toincrease the speed change step by one step it was necessary that thenumber of gears in the composite or single planetary gear train beincreased and additional mating members be provided, whereas the presentinvention eliminates the need to increase the planetary gears and onlyrequires additional brake means to be provided to fix one input memberin the conventional planetary gears. This leads to a lower cost andsimpler procedures involved to provide the entire device.

What is claimed is:

1. A speed change gear device consisting essentially of a first and asecond clutch means provided between an input and an output shaftdisposed concentrically within a gear case, and a planetary gear trainhaving a first and a second input gear member connected, respectively,to said first and second clutch means, an output gear member connectedto said output shaft, and a first and second brake means for holdingsaid first and second input gear members, respectively, whereby acombination of speed change ratios of required steps is obtained at theoutput shaft by selective actuation of said clutch and brake means.

2. A speed change gear device according to claim 1, wherein saidplanetary gear train comprises three sun gears each of which areindependently rotatable, a long pinion having three gear portions inrespective engagement with two sun gears and an idle gear, the idle gearbeing related to one of the sun gears and said long pinion, a carrierrotatably supporting said long pinion and said idle gear, whereby a sungear engaged with the idle gear is connected to said second clutchmeans, the remaining two sun gears being connected to said first clutchmeans and said output shaft, respectively.

3. A speed change gear device according to claim 1, wherein theplanetary gear train includes a sun gear, and two sets of a gear trainincluding a pinion gear engaged with the sun gear, a ring gear engagedwith the pinion gear, and a carrier rotatably supporting said piniongear.

4. A speed change gear device according to claim 3, wherein the sun gearis connected to the second clutch means, the ring gear of a first one ofsaid gear trains is connected to the first clutch means, and the carrierof one gear train and the ring gear of the other gear train areconnected to the output shaft.

5. A speed change gear device according to claim 3, wherein the sun gearis connected to the second clutch means, the ring gear of the secondgear train is connected to the first clutch means, and the ring gearofthe first gear train and the carrier of the second gear train areconnected to the output shaft.

6. A speed change gear device according to claim 1, wherein theplanetary gear train comprises, in combination, four sun gears, each ofwhich are independently rotatable, and idle gear having two integrallyformed gear portions in engagement with two of the four sun gears, along pinion having three integrally formed gear portions in engagementwith the remaining two sun gears and said idle gear, respectively, acarrier rotatably supporting the long pinion and the idle gear, one ofsaid two sun gears in engagement with said gear portions of said idlegear being connected to the first clutch means, the remaining one ofsaid two sun gears in engagement with said gear portions of said idlegears being connected to the output shaft, and any one of the remainingtwo sun gears being connected to the second clutch means.

1. A speed change gear device consisting essentially of a first and asecond clutch means provided between an input and an output shaftdisposed concentrically within a gear case, and a planetary gear trainhaving a first and a second input gear member connected, respectively,to said first and second clutch means, an output gear member connectedto said output shaft, and a first and second brake means for holdingsaid first and second input gear members, respectively, whereby acombination of speed change ratios of required steps is obtained at theoutput shaft by selective actuation of said clutch and brake means.
 2. Aspeed change gear device according to claim 1, wherein said planetarygear train comprises three sun gears each of which are independentlyrotatable, a long pinion having three gear portions in respectiveengagement with two sun gears and an idle gear, the idle gear beingrelated to one of the sun gears and said long pinion, a carrierrotatably supporting said long pinion and said idle gear, whereby a sungear engaged with the idle gear is connected to said second clutchmeans, the remaining two sun gears being connected to said first clutchmeans and said output shaft, respectively.
 3. A speed change gear deviceaccording to claim 1, wherein the planetary gear train includes a sungear, and two sets of a gear train including a pinion gear engaged withthe sun gear, a ring gear engaged with the pinion gear, and a carrierrotatably supporting said pinion gear.
 4. A speed change gear deviceaccording to claim 3, wherein the sun gear is connected to the secondclutch means, the ring gear of a first one of said gear trains isconnected to the first clutch means, and the carrier of one gear trainand the ring gear of the other gear train are connected to the outputshaft.
 5. A speed change gear device according to claim 3, wherein thesun gear is connected to the second clutch means, the ring gear of thesecond gear train is connected to the first clutch means, and the ringgear of the first gear train and the carrier of the second gear trainare connected to the output shaft.
 6. A speed change gear deviceaccording to claim 1, wherein the planetary gear train comprises, incombination, four sun gears, each of which are independently rotatable,and idle gear having two integrally formed gear portions in engagementwith two of the four sun gears, a long pinion having three integrallyformed gear portions in engagement with the remaining two sun gears andsaid idle gear, respectively, a carrier rotatably supporting the longpinion and the idle gear, one of said two sun gears in engagement withsaid gear portions of said idle gear being connected to the first clutchmeans, the remaining one of said two sun gears in engagement with saidgear portions of said idle gears being connected to the output shaft,and any one of the remaining two sun gears being connected to the secondclutch means.